#include <stdio.h>
#include <stdlib.h>

int m, n;

void swap (int *np, int *mp) {
  
  int tmp;

  tmp = *np;
  *np= *mp;
  *mp = tmp;

}

int main () {
  

  m = 1;
  n = 2;

  swap (&n, &m);

  printf ("m = %d, n = %d\n", m, n);
  
  exit (0);
}